Alladi Ramakrishnan Hall

Abhimanyu Susobhanan

TIFR

Pulsar timing array experiments aim to detect nanohertz gravitational waves (GWs) by precise timing of an ensemble of millisecond pulsars. Times of arrival (TOAs) of pulsar pulses are modulated in the presence of a GW, by an amount proportional to the antiderivative of the GW amplitude. In this talk, I present our latest results on efficient computation of GW-induced pulsar timing residuals due to eccentric supermassive black hole binaries. GW-induced timing residuals due to low-eccentricity binaries can be very efficiently computed using analytic post-circular waveforms developed by Boetzel et al. 2017 incorporating advance of periastron in a post-Newtonian (PN) accurate manner. I also introduce a novel semi-analytic solution to quadrupolar order orbital evolution equations which enables efficient computation of the Pulsar term in the timing residuals. This efficient solution also enables the computation of numerical arbitrary-eccentricity timing residuals incorporating exactly the reactive orbital evolution and advance of periastron. These results will be used to search for eccentric supermassive binaries in the International Pulsar Timing Array data.